Strap-type clamp



June 26, 1928.

W. H. VIBBER STRAP TYPE CLAMP Filed Sept. 29, 1926 fiWf. VM @MMIMM Patented June 26, 1928.

UNITED STATES WHEELER H 'VIBBEB, OF N LONDON, CONNECTICUT.

STRAP-TYPE CLAMP.

Application filed September 29, 1926. Serial No. 138,398.

My invention relates to an improvement in strap-type clamps, particularly designed for use in grounding electric wire, but also available for use in a variet of situations where it is desired to apply a xture to a tube or pipe, the object of my invention bemg to increase the efliciency and prolong the hfe of clamps of the strap-type.

With these ends in view, my invention consists in a strap-type clamp having a substantially-circular body and two perforated ends, one of which is bent to produce an anchoring-abutment over which the other strap-end is deflected to form a bight for relievmg the strain upon the clamping-screw, which passes transversely through the said strap-ends at a point between its circular body and the said anchoring-abutment.

My invention further consists in a straptype clamp characterized as above in combination with a deflecting-member ap lied to one of the strap-ends so as to de ect the same over the anchoring-abutment of the other strap-end. I

My invention further consists in a straptype clamp characterized as demribed, provided with a deflector perforated for the passage of a clamping-screw and having a deflecting-rib-for deflecting the substantiallystraight end of the strap over the anchoringabutment of the other end thereof.

My invention further consists in a straptype clamp having certain details of construction and combinations of parts as will be hereinafter described and particularly pointed out in the claims.

In the accompanying drawings:

Fig. 1 is a view in edge elevation of one form which my strap-type clamp may as sume;

Fig. 2 is a view thereof in side elevation;

Fig. 3 is a view in side elevation of another form which my improved clamp may assume;

Fig. 4 is a. view thereof in longitudinal section on the line 4-4 of Fig. 3;

Fig. 5 is a detached face view of the deflector employed in the construction shown in the preceding figures;

Fig. 6 is an edge view thereof;

Fig. 7 is a view in elevation of still another form which my improved clamp may assume; and

Fig. 8 is a view thereof in longitudinal section on the line 88 of Fig. 7.

In carrying out my invention, as shown in ribs 15 upon Figs. 1 and 2, I employ a sheet-metal strap bent to produce a substantially-circular body 10 and strap-ends 11 and 12, which latter are perforated in the usual manner for the reception of a threaded clamping-screw 13, by means of which the said body is tightly clasped upon the pipe or rod to which the clamp is applied for making an electrical ground. With such a strap I employ a substantially-rectangular deflector 14 having corresponding edges of its opposite faces, a perforation 16 for the reception of the clamping-screw 13 and a soldering-lug for the attachment of the groundingwire 18. For the reception of the usual clamping-nut 19, the strap-end 11 is turned outward arallel with the axis of the screw and then inward at a right angle to the said axis, so as to form, as it were, a housing for the nut, as clearly shown in Fig. 1. The strap-end 11, as thus bent, forms an anchoring-abutment 20, over which the strap-end 12 is forced and so bent, as at 21, by the engagement with it of one of the deflecting-ribs 15 of the deflector, according to the position thereof when the clamping-screw 13 is turned home to draw the strap-ends together and clasp the body of the strap upon the rod or tube, as the case may be.

By bendin the strap-end 12, as described, over the anc oring-abutment 20, a bight is formed in the strap-end 12 and the strain largely removed therefrom and hence from the screw, which is thus prevented from being bent and having its threads broken down or deformed. Also, the perforation or screw-hole in the strap-end is prevented from being elongated, which is tantamount to lengthening the strap as a whole and so impairing its gripping power. Also, the parallelism of the main portions of the strap-ends is maintained, with obvious advantage, since if the strap-ends form even an acute angle with respect to each other, proper seats are not provided for the head of the clamping-screw and its nut.

In the modified construction shown in Figs. 3 and 4, the sheet-metal strap is bent to form a substantially-circular body 22 and strap-ends 23 and 24, which latter are perforated as. usual for the reception of a clamping-screw 25, which also passes through the deflector 14 already described. In this construction, the clamping-nut 19 is dispensed with and the strap-end 24 bent upon itself to form an anchoring-abutment 26 parallel with the axis of the screw 25 and positioned with respect to the deflecting-ribs 15 of the deflector 14, so that, when the clamping-screw is turned home in the bracket 27, which takes the place of the clamping-nut 19, the strap-end 23 is deflected over the abutment 26, so as to form a bight to reduce the strain upon the screw and prevent the elongation of the perforation of the strap-end 23.

The lower end of the said bracket 27 is provided with an internally-threaded sleeve 28 for the reception of the threaded end of a conduit, which is not shown.

In the construction shown by Figs. 7 and 8, a sheet-metal strap is bent to form a sub stantially circular body 29 having strap-ends 30 and 31, the latter having its extreme end turned inward at a right angle to form an anchoring-abutment 32 (parallel with the axis of the screw 13 an positioned to be closely adjacent to one of the ribs 15 of the deflector 14, as shown in F ig. 3. In this construction, as in the modification shown by Figs. 3 and 4, the clamping-nut 19 is replaced by a bracket 33 having a threaded opening 34 for the reception of the clamping-screw 13, the said bracket being provided at its lower end with an internallythreaded sleeve 35 for the reception of a threaded conduit. In this construction, a rivet 36 is employed for securing the strapend 31 to the bracket 33. Vhen the screw 13 is turned home, the rib 15 and the anchor ing-abutment 32 unite to deflect the strapend 30, as at 37, whereby a bight is formed to minimize the draft of the strap-end 30 upon the screw 13.

In each of the constructions described, the tendency of the draft upon one of the strapends to strain and deform the clamping screw is minimized, as well as the elongation of the screw-hole in the said strap-end, which, when it takes place, virtually lengthens the strap and proportionately decreases its ripping-power.

oreover, under my improved construction, the strap-ends are virtually stabilized in parallelism, which provides a better seat for the head of the clamping-screw and for the clamping-nut, or whatever takes its place, than can be secured when the strap-ends are inclined toward each other, rather than maintained in parallelism, as under my invention.

I claim:

1. A strap-type clamp having a sheetmetal strap bent to form a substantiallycircular body and two ends, which latter are perforated and one of which is bent to produce an anchoring-abutment over which the other strap-end is deflected to form a bight for relieving the strain upon the clampingscrew which passes transversely through the said strap-ends at a point between the said body and the said anchoring-abutment.

2. A strap-type clamp having a sheetmetal strap bent to form a substantiallycircular body and two ends, which latter are perforated, a clamping-screw passing through the said ends for drawing them together, one of the said ends being bent to produce an anchoring-abutment, and a deflector mounted upon the said screw and adapted to deflect the strap-end adjacent to it over the anchoring-abutment of the other strap-end, whereby a bight is formed for relieving the tension upon the screw.

3. A strap-type clamp havinv a sheetmetal strap bent to form a substantiallycircular body and two ends, which latter are perforated, a clamping-screw passing through the said ends, one of which is transversely bent to produce an anchoring-abutment, and a deflector mounted upon the said screw and provided with a deflectingmib which deflects the strap-end adjacent to it over the anchoring-abutment of the other strap-end to form a bight therefor.

4. A strap-type ground-clamp having a sheet-metal strap bent to form a substantially-circular body and two ends, which latter are perforated, a clamping-screw passing through the said ends, one of which is bent to form an anchoring-abutment, and a deflector rovided with a soldering-lug for the attacim'ent of a grounding-wire, the said deflector being mounted upon the screw in position'to deflect the adjacent strap-end over the said anchoring-abutment.

5. In a strap-type ground-clamp, the combination with a sheet-metal strap bent to form a body and two ends, which latter are perforated, of a clamping-screw passing through the perforated strap-ends, one of which is bent to form an anchoring abutment, a reversible deflector provided upon the edges of its opposite faces with deflectingribs, formed with a perforation by which it is mounted upon the screw and with a soldering-lug, the said deflector, by the engagement of one of its ribs with the adjacent strap-end, crowding the same over the anchoring-abutment of the other strap-end to produce a bight in the said adjacent strapend, whereby the same is relieved of strain.

In testimony whereof, I have signed this specification.

WHEELER H. VIBBER. 

